Brain-immune interactions in sleep

Aquilaria sinensis leaf tea affects the immune system and increases sleep in zebrafish

The importance of adequate sleep for good health cannot be overstated. Excessive light exposure at night disrupts sleep, therefore, it is important to find more healthy drinks that can promote sleep under sleep-disturbed conditions. The present study investigated the use of A. sinensis (Lour.) Spreng leaf tea, a natural product, to reduce the adverse effects of nighttime light on sleep. Here, Aquilaria sinensis leaf tea at 1.0 and 1.5 g/L significantly increased sleep time in zebrafish larvae (5-7 dpf) with light-induced sleep disturbance. Transcriptome sequencing and qRT-PCR analysis revealed a decrease in the immune-related genes, such as nfkbiab, tnfrsf1a, nfkbiaa, il1b, traf3, and cd40 in the 1.5 g/L Aquilaria sinensis leaf tea treatment group. In addition, a gene associated with sleep, bhlhe41, showed a significant decrease. Moreover, Aquilaria sinensis leaf tea suppressed the increase in neutrophils of Tg(mpo:GFP) zebrafish under sleep-disturbed conditions, indicating its ability to improve the immune response. Widely targeted metabolic profiling of the Aquilaria sinensis tea using ultra-performance liquid chromatography coupled with electrospray tandem mass spectrometry (UPLC-ESI-MS/MS) revealed flavonoids as the predominant component. Network pharmacological and molecular docking analyses suggested that the flavonoids quercetin and eupatilin in Aquilaria sinensis leaf tea improved the sleep of zebrafish by interacting with il1b and cd40 genes under light exposure at night. Therefore, the results of the study provide evidence supporting the notion that Aquilaria sinensis leaf tea has a positive impact on sleep patterns in zebrafish subjected to disrupted sleep due to nighttime light exposure. This suggests that the utilization of Aquilaria sinensis leaf tea as a potential therapeutic intervention for sleep disturbances induced by light may yield advantageous outcomes.

Healthy lifestyles and wellbeing reduce neuroinflammation and prevent neurodegenerative and psychiatric disorders

Since the mid-20th century, Western societies have considered productivity and economic outcomes are more important than focusing on people's health and wellbeing. This focus has created lifestyles with high stress levels, associated with overconsumption of unhealthy foods and little exercise, which negatively affect people's lives, and subsequently lead to the development of pathologies, including neurodegenerative and psychiatric disorders. Prioritizing a healthy lifestyle to maintain wellbeing may slow the onset or reduce the severity of pathologies. It is a win-win for everyone; for societies and for individuals. A balanced lifestyle is increasingly being adopted globally, with many doctors encouraging meditation and prescribing non-pharmaceutical interventions to treat depression. In psychiatric and neurodegenerative disorders, the inflammatory response system of the brain (neuroinflammation) is activated. Many risks factors are now known to be linked to neuroinflammation such as stress, pollution, and a high saturated and trans fat diet. On the other hand, many studies have linked healthy habits and anti-inflammatory products with lower levels of neuroinflammation and a reduced risk of neurodegenerative and psychiatric disorders. Sharing risk and protective factors is critical so that individuals can make informed choices that promote positive aging throughout their lifespan. Most strategies to manage neurodegenerative diseases are palliative because neurodegeneration has been progressing silently for decades before symptoms appear. Here, we focus on preventing neurodegenerative diseases by adopting an integrated "healthy" lifestyle approach. This review summarizes the role of neuroinflammation on risk and protective factors of neurodegenerative and psychiatric disorders.

The CSHQ-DE Questionnaire Uncovers Relevant Sleep Disorders in Children and Adolescents with Long COVID

Acute SARS-CoV-2 infections in children and adolescents are usually mild. However, they can suffer from ongoing symptoms, generally referred to as long COVID. Sleep disorders are one of the most frequent complaints in long COVID although precise data are missing. We assessed the sleep behavior of children and adolescents who presented at our outpatient clinic between January 2021 and May 2022 with the Children’s Sleep Habits Questionnaire (CSHQ-DE). We compared the sleep behavior at three different time points: pre-COVID-19; post-COVID-19 at the initial presentation; and post-COVID-19 at re-presentation. Data from 45 patients were analyzed. Of those, 64% were female and the median age was 10 years (range: 0–18 years). Asymptomatic or mild COVID-19 disease was experienced in 89% of patients; 11% experienced moderate disease. The initial presentation occurred at a median of 20.4 weeks (6 weeks–14 months) after the infection. The CSHQ-DE score increased significantly from pre-COVID-19 (45.82 ± 8.7 points) to post-COVID-19 (49.40 ± 8.3 points; p ≤ 0.01). The score then normalized at re-presentation (46.98 ± 7.8; p = 0.1). The greatest changes were seen in the CSHQ-DE subscale score “daytime sleepiness”. Our data showed that children and adolescents with long COVID often suffer from sleep disturbances. For most children and adolescents, these sleep disorders decreased over time without any further medical intervention aside from a basic sleep consultation.

Interplay of Environmental, Individual and Genetic Factors in Rheumatoid Arthritis Provocation

In this review, we explore systemization of knowledge about the triggering effects of non-genetic factors in pathogenic mechanisms that contribute to the development of rheumatoid arthritis (RA). Possible mechanisms involving environmental and individual factors in RA pathogenesis were analyzed, namely, infections, mental stress, sleep deprivation ecology, age, perinatal and gender factors, eating habits, obesity and smoking. The non-genetic factors modulate basic processes in the body with the impact of these factors being non-specific, but these common challenges may be decisive for advancement of the disease in the predisposed body at risk for RA. The provocation of this particular disease is associated with the presence of congenital loci minoris resistentia. The more frequent non-genetic factors form tangles of interdependent relationships and, thereby, several interdependent external factors hit one vulnerable basic process at once, either provoking or reinforcing each other. Understanding the specific mechanisms by which environmental and individual factors impact an individual under RA risk in the preclinical stages can contribute to early disease diagnosis and, if the factor is modifiable, might be useful for the prevention or delay of its development.

Possible Neuropathology of Sleep Disturbance Linking to Alzheimer's Disease: Astrocytic and Microglial Roles

Sleep disturbances not only deteriorate Alzheimer’s disease (AD) progress by affecting cognitive states but also accelerate the neuropathological changes of AD. Astrocytes and microglia are the principal players in the regulation of both sleep and AD. We proposed that possible astrocyte-mediated and microglia-mediated neuropathological changes of sleep disturbances linked to AD, such as astrocytic adenosinergic A1, A2, and A3 regulation; astrocytic dopamine and serotonin; astrocyte-mediated proinflammatory status (TNFα); sleep disturbance-attenuated microglial CX3CR1 and P2Y12; microglial Iba-1 and astrocytic glial fibrillary acidic protein (GFAP); and microglia-mediated proinflammatory status (IL-1b, IL-6, IL-10, and TNFα). Furthermore, astrocytic and microglial amyloid beta (Aβ) and tau in AD were reviewed, such as astrocytic Aβ interaction in AD; astrocyte-mediated proinflammation in AD; astrocytic interaction with Aβ in the central nervous system (CNS); astrocytic apolipoprotein E (ApoE)-induced Aβ clearance in AD, as well as microglial Aβ clearance and aggregation in AD; proinflammation-induced microglial Aβ aggregation in AD; microglial-accumulated tau in AD; and microglial ApoE and TREM2 in AD. We reviewed astrocytic and microglial roles in AD and sleep, such as astrocyte/microglial-mediated proinflammation in AD and sleep; astrocytic ApoE in sleep and AD; and accumulated Aβ-triggered synaptic abnormalities in sleep disturbance. This review will provide a possible astrocytic and microglial mechanism of sleep disturbance linked to AD.

[Cognitive disorders and sleep disturbances in long COVID]

Hintergrund

In den letzten 2 Jahren der COVID-19(„coronavirus disease 2019“)-Pandemie ist das Wissen um Langzeitfolgen der Erkrankung, das sog. „Long-COVID“, rapide gewachsen. Es bleiben jedoch noch viele Fragen offen, v. a. was die Ursachen überdauernder Beschwerden und ihre Prognose betrifft. Kognitive Störungen und Schlafstörungen gehören zu den häufig beklagten Beschwerden. Beide gehen mit starkem Leidensdruck und deutlicher Alltagsbeeinträchtigung einher.

Ziel der Arbeit

Wie ist die Datenlage zum Auftreten kognitiver Störungen und Schlafstörungen bei Long-COVID? Welches sind Einflussfaktoren und was ist bekannt zum Verlauf und zu möglichen zugrunde liegenden Mechanismen? Welche Therapieoptionen gibt es?

Material und Methode

In einem narrativen Review werden die wichtigsten Befunde zu kognitiven Störungen und Schlafstörungen bei Long-COVID dargestellt. Es wird ein Überblick gegeben über die Kohortenstudien mit Daten zu Prävalenz und Einflussfaktoren beider Symptomkomplexe. Es werden derzeitige Kenntnisse und Hypothesen zu pathophysiologischen Mechanismen dargestellt und ein Ausblick auf Behandlungsansätze gegeben.

Ergebnisse

Etwa ein Fünftel der Betroffenen berichtet mehr als 3 Monate nach einer SARS-CoV-2(„severe acute respiratory syndrome coronavirus 2“)-Infektion über kognitive Einschränkungen, etwa ein Drittel über Schlafstörungen, wobei es neben insomnischen auch zu hypersomnische Beschwerden kommt. Kognitive Störungen und Schlafstörungen treten bei Betroffenen aller Schweregrade auf. Es gibt Hinweise auf eine Besserung kognitiver Defizite im Verlauf, allerdings sind weitere Längsschnittstudien notwendig.

Diskussion

Neben der Prognose sind die zugrunde liegenden Krankheitsmechanismen noch unzureichend verstanden. Zudem besteht großer Forschungsbedarf zur Wirksamkeit und zu spezifischen Wirkfaktoren therapeutischer Interventionen.

An important link between the gut microbiota and the circadian rhythm: imply for treatments of circadian rhythm sleep disorder

Currently, gut microbiota living in the gastrointestinal tract, plays an important role in regulating host's sleep and circadian rhythms. As a tool, gut microbiota has great potential for treating circadian disturbance and circadian insomnia. However, the relationship between gut microbiota and circadian rhythms is still unclear, and the mechanism of action has still been the focus of microbiome research. Therefore, this article summarizes the current evidences associating gut microbiota with factors that impact host circadian rhythms neurology sleep disorder. Moreover, we discuss the changes to these systems in sleep disorder and the potential mechanism of intestinal microbiota in regulating circadian rhythms neurology sleep disorder via microbial metabolites. Meanwhile, based on the role of intestinal flora, it is provided a novel insight into circadian related insomnia and will be benefit the dietary treatment of circadian disturbance and the circadian related insomnia.

Staying Physically Active Is Associated with Better Mental Health and Sleep Health Outcomes during the Initial Period of COVID-19 Induced Nation-Wide Lockdown in Jordan

Jordan, a Middle Eastern country, initially responded to an outbreak of COVID-19 cases within its own borders by imposing a 7-week strict lockdown and closure of international and domestic travel. Such measures drastically influenced lifestyle behaviors of the population. This study aimed to investigate the prevalence of physical activity, and its association with mental and sleep health outcomes among Jordanians during a period of COVID-19 induced lockdown. Validated questionnaires were administered using a web-based platform to evaluate moderate-to-vigorous physical activity (MVPA), anxiety and depressive symptoms, sleep health, and sociodemographic characteristics. A modified Poisson regression model with robust error variance was used to estimate adjusted prevalence ratios (aPRs) and 95% confidence intervals (CIs). Compared to participants who met the guidelines, those who did not had significantly higher prevalence of moderate or severe anxiety symptoms than that of minimal or mild anxiety symptoms and increased depressive symptoms. Insufficient MVPA was associated with higher prevalence of poor sleep quality, short sleep duration (<7 h) and sleep problems. Overall, sufficient MVPA was associated with better mental and sleep health during the COVID-19 induced nation-wide lockdown in Jordan. While further research is necessary, promoting physical activity during the lockdown could potentially improve mental and sleep health outcomes among the population.

Sleep Quality's Effect on Vigilance and Perceptual Ability in Adolescent and Adult Athletes

The aim of the study was to investigate the effect of sleep quality in cognitive domains of perceptual ability after exhausting exercise in adolescent and adult athletes. Eighty-six male professional soccer players were included in our study and divided into two groups: adolescents (age: 17.3 ± 0.2 yrs, body mass: 68.9 ± 7.9 kg, body fat: 9.9 ± 3.6 %) versus adults (age: 26.3 ± 5.2 yrs, body mass: 76.5 ± 7.2 kg, body fat: 10.3 ± 3.1 %). For each athlete, prior to cardiopulmonary exercise testing (CPET), anthropometric and morphological characteristics were recorded and Pittsburgh Sleep Quality Index (PSQI) questionnaire was answered. Immediately after CPET, all athletes underwent the perceptual ability test (PATest) for 30 sec and the sum of hits (rep/30 sec) and the time between a visual stimulus and the following stimulus (mean reaction time; RT, sec) were recorded. Oxygen uptake in maximal effort and in anaerobic threshold showed differences between hits (P=0.037) and RT (P=0.025). The variable of PSQI questionnaire "had bad dreams" showed correlation with hits (P=0.021) and RT (P=0.011) and the RT showed correlation with variables "cannot breathe comfortably" (P=0.041) and "...enthusiasm to get things done" (P=0.041). Adolescents showed poorer sleep quality (PSQI score: 5.7 ± 3.6 vs. 2.4 ± 2.6) compared to adults and slower reaction time (0.9 ± 0.1 vs. 0.8 ± 0.1 sec, P=0.029) compared to adolescent athletes with PSQI score ≥5.5. The variable of PSQI score in adolescents is related to HR in maximal effort (r = -0.364, P=0.032) and in adults is related to speed (r = -0.335, P=0.016). Perceptual ability, which requires sustained attention, vigilance, and motor coordination, is often negatively affected by restricted sleep, especially in adolescents.

Anxiety and depressive symptoms are associated with poor sleep health during a period of COVID-19-induced nationwide lockdown: a cross-sectional analysis of adults in Jordan

BACKGROUND

Jordan, a Middle Eastern country, declared a state of national emergency due to COVID-19 and a strict nationwide lockdown on 17 March 2020, banning all travel and movement around the country, potentially impacting mental health. This study sought to investigate the association between mental health (eg, anxiety and depressive symptoms) and sleep health among a sample of Jordanians living through a state of COVID-19-induced nationwide lockdown.

METHODS

Using Facebook, participants (n=1240) in Jordan in March 2020 were recruited and direct to a web-based survey measuring anxiety (items from General Anxiety Disorder 7-item (GAD-7) scale instrument), depressive symptoms (items from Center for Epidemiologic Studies Depression Scale), sleep health (items from the Pittsburgh Sleep Quality Index) and sociodemographic. A modified Poisson regression model with robust error variance. Adjusted prevalence ratios (aPRs) and 95% CIs were estimated to examine how anxiety and depressive symptoms may affect different dimensions of sleep health: (1) poor sleep quality, (2) short sleep duration, (3) encountering sleep problems.

RESULTS

The majority of participants reported having experienced mild (33.8%), moderate (12.9%) or severe (6.3%) levels of anxiety during lockdown, and nearly half of respondents reported depressive symptoms during lockdown. Similarly, over 60% of participants reported having experienced at least one sleep problem in the last week, and nearly half reported having had short sleep duration. Importantly, anxiety was associated with poor sleep health outcomes. For example, corresponding to the dose-response relationship between anxiety and sleep health outcomes, those reporting severe anxiety were the most likely to experience poor sleep quality (aPR =8.95; 95% CI=6.12 to 13.08), short sleep duration (aPR =2.23; 95% CI=1.91 to 2.61) and at least one problem sleep problem (aPR=1.73; 95% CI=1.54 to 1.95). Moreover, depressive symptoms were also associated with poor sleep health outcomes. As compared with scoring in the first quartile, scoring fourth quartile was associated with poor sleep quality (aPR=11.82; 95% CI=6.64 to 21.04), short sleep duration (aPR=1.87; 95% CI=1.58 to 2.22), and experiencing at least one sleep problem (aPR=1.90; 95% CI=1.66 to 2.18).

CONCLUSIONS

Increased levels of anxiety and depressive symptoms can negatively influence sleep health among a sample of Jordanian adults living in a state of COVID-19-induced nationwide lockdown.

The Bidirectional Relationship Between Sleep and Inflammation Links Traumatic Brain Injury and Alzheimer's Disease

Traumatic brain injury (TBI) and Alzheimer's disease (AD) are diseases during which the fine-tuned autoregulation of the brain is lost. Despite the stark contrast in their causal mechanisms, both TBI and AD are conditions which elicit a neuroinflammatory response that is coupled with physical, cognitive, and affective symptoms. One commonly reported symptom in both TBI and AD patients is disturbed sleep. Sleep is regulated by circadian and homeostatic processes such that pathological inflammation may disrupt the chemical signaling required to maintain a healthy sleep profile. In this way, immune system activation can influence sleep physiology. Conversely, sleep disturbances can exacerbate symptoms or increase the risk of inflammatory/neurodegenerative diseases. Both TBI and AD are worsened by a chronic pro-inflammatory microenvironment which exacerbates symptoms and worsens clinical outcome. Herein, a positive feedback loop of chronic inflammation and sleep disturbances is initiated. In this review, the bidirectional relationship between sleep disturbances and inflammation is discussed, where chronic inflammation associated with TBI and AD can lead to sleep disturbances and exacerbated neuropathology. The role of microglia and cytokines in sleep disturbances associated with these diseases is highlighted. The proposed sleep and inflammation-mediated link between TBI and AD presents an opportunity for a multifaceted approach to clinical intervention.

Inpatient admission following anterior cruciate ligament reconstruction is associated with higher postoperative complications

PURPOSE

To compare the occurrence of short-term postoperative complications between inpatient and outpatient anterior cruciate ligament reconstruction.

METHODS

The ACS National Surgical Quality Improvement Program (NSQIP) database was utilized to identify patients undergoing arthroscopic anterior cruciate ligament reconstruction (ACLR) from 2007 to 2017. A total of 18,052 patients were available for analysis following application of exclusion criteria. Patients were categorized based on location of surgery. Inpatients and outpatient ACLR groups were matched by demographics and preoperative laboratory values and differences in 30-day complication rates following surgery were assessed. Significance was set with alpha < 0.05.

RESULTS

From 2007 to 2017, there was an increasing frequency for outpatient ACLR (p < 0.001), while the incidence of inpatient ACLR remained largely constant (n.s). Groups were matched to include 1818 patients in each cohort. Within the first 30 days of surgery, patients in the inpatient ACLR group experienced significantly greater rates of superficial incisional SSI (0.6% vs 0.1%, p = 0.026) and composite surgical complications (0.6% vs 0.2%, p = 0.019), as well as a greater rate of reoperation (0.7% vs 0.2%, p = 0.029). Inpatient procedures also demonstrated a greater rate of deep surgical incisional SSI (0.2% vs 0.0%, n.s) and readmission to hospital (0.8% vs 0.7%, n.s).Outpatient ACLR procedures were also associated with a significantly greater relative value unit (RVU)/h compared with inpatient ACLRs (0.17 vs 0.14, p < 0.001).

CONCLUSIONS

Inpatient ACLR may have an increased risk of postoperative complications compared to outpatient ACLR during the short-term postoperative period. Although some patients may require admission post-operatively for medical and/or pain management, doing so is not necessarily without a degree of risk.

LEVEL OF EVIDENCE

III.

Cell-specific conditional deletion of interleukin-1 (IL-1) ligands and its receptors: a new toolbox to study the role of IL-1 in health and disease

The pro-inflammatory cytokine interleukin-1 (IL-1) plays a key role in many physiological processes and during the inflammatory and immune response to most common diseases. IL-1 exists as two agonists, IL-1α and IL-1β that bind to the only signaling IL-1 type 1 receptor (IL-1R1), while a second decoy IL-1 type 2 receptor (IL-1R2) binds both forms of IL-1 without inducing cell signaling. The field of immunology and inflammation research has, over the past 35 years, unraveled many mechanisms of IL-1 actions, through in vitro manipulation of the IL-1 system or by using genetically engineered mouse models that lack either member of the IL-1 family in ubiquitous constitutive manner. However, the limitation of global mouse knockout technology has significantly hampered our understanding of the precise mechanisms of IL-1 actions in animal models of disease. Here we report and review the recent generation of new conditional mouse mutants in which exons of Il1a, Il1b, Il1r1, and Il1r2 genes flanked by loxP sites (fl/fl) can be deleted in cell-/tissue-specific constitutive or inducible manner by Cre recombinase expression. Hence, IL-1αfl/fl, IL-1βfl/fl, IL-1R1fl/fl, and IL-1R2fl/fl mice constitute a new toolbox that will provide a step change in our understanding of the cell-specific role of IL-1 and its receptor in health and disease and the potential development of targeted IL-1 therapies.

Short-term sleep deprivation in mice induces B cell migration to the brain compartment

Increasing evidence highlight the involvement of immune cells in brain activity and its dysfunction. The brain's immune compartment is a dynamic ensemble of cells that can fluctuate even in naive animals. However, the dynamics and factors that can affect the composition of immune cells in the naive brain are largely unknown. Here, we examined whether acute sleep deprivation can affect the brain's immune compartment (parenchyma, meninges, and choroid plexus). Using high-dimensional mass cytometry analysis, we broadly characterized the effects of short-term sleep deprivation on the immune composition in the mouse brain. We found that after 6 h of sleep deprivation, there was a significant increase in the abundance of B cells in the brain compartment. This effect can be accounted for, at least in part, by the elevated expression of the migration-related receptor, CXCR5, on B cells and its ligand, cxcl13, in the meninges following sleep deprivation. Thus, our study reveals that short-term sleep deprivation affects the brain's immune compartment, offering a new insight into how sleep disorders can affect brain function and potentially contribute to neurodegeneration and neuroinflammation.

Association of sleep impairments and gastrointestinal disorders in the context of the visceral theory of sleep

It was noticed long ago that sleep disorders or interruptions to the normal sleep pattern were associated with various gastrointestinal disorders. We review the studies which established the causal link between these disorders and sleep impairment. However, the mechanism of interactions between the quality of sleep and gastrointestinal pathophysiology remained unclear. Recently, the visceral theory of sleep was formulated. This theory proposes that the same brain structures, and particularly the same cortical sensory areas, which in wakefulness are involved in processing of the exteroceptive information, switch during sleep to the processing of information coming from various visceral systems. We review the studies which demonstrated that neurons of the various cortical areas (occipital, parietal, frontal) during sleep began to fire in response to activation coming from the stomach and small intestine. These data demonstrate that, during sleep, the computational power of the central nervous system, including all cortical areas, is engaged in restoration of visceral systems. Thus, the general mechanism of the interaction between quality of sleep and health became clear.

A mechanism for sickness sleep: lessons from invertebrates

During health, animal sleep is regulated by an internal clock and by the duration of prior wakefulness. During sickness, sleep is regulated by cytokines released from either peripheral cells or from cells within the nervous system. These cytokines regulate central nervous system neurons to induce sleep. Recent research in the invertebrates Caenorhabditis elegans and Drosophila melanogaster has led to new insights into the mechanism of sleep during sickness. Sickness is triggered by exposure to environments such as infection, heat, or ultraviolet light irradiation, all of which cause cellular stress. Epidermal growth factor is released from stressed cells and signals to activate central neuroendocrine cell(s). These neuron(s) release neuropeptides including those containing an amidated arginine(R)-phenylalanine(F) motif at their C-termini (RFamide peptides). Importantly, mechanisms regulating sickness sleep are partially distinct from those regulating healthy sleep. We will here review key findings that have elucidated the central neuroendocrine mechanism of sleep during sickness. Adaptive mechanisms employed in the control of sickness sleep may play a role in correcting cellular homeostasis after various insults. We speculate that these mechanisms may play a maladaptive role in human pathological conditions such as in the fatigue and anorexia associated with autoimmune diseases, with major depression, and with unexplained chronic fatigue.

Longitudinal and Temporal Associations Between Daily Pain and Sleep Patterns After Major Pediatric Surgery

Approximately 20% of children develop persistent pain after major surgery. Sleep disruption has been implicated as a predictor of children's acute postsurgical pain. However, perioperative sleep patterns have not been longitudinally assessed, and the role of sleep in persistence of postsurgical pain has not been explored. We aimed to examine sleep patterns over 4 months in children having major surgery, and temporal relationships between daily sleep and pain. Sixty children age 10 to 18 (mean = 14.7) years having major surgery completed 7 days of actigraphy sleep monitoring (sleep duration, efficiency), twice daily electronic diaries (sleep quality, pain intensity, medication use), and validated questionnaires at presurgery, 2 weeks, and 4 months postsurgery. Generalized linear models, controlling for age, sex, naps, and medication, showed sleep quality (β [B] = -.88, P < .001) and efficiency (B = -1.50, P = .036) were significantly reduced at 2 weeks compared with presurgery, and returned to baseline by 4 months. Poorer night-time sleep quality was significantly associated with greater next day pain intensity (B = -.15, P = .005). Sleep duration and efficiency were not associated with subsequent pain; daytime pain was not associated with subsequent sleep. Findings suggest sleep quality may be an important target for intervention after surgery in children; research is needed to understand how other sleep parameters may relate to recovery.

PERSPECTIVE

This study assessed longitudinal sleep patterns over 4 months after major pediatric surgery using actigraphy, diaries, and validated measures. Sleep quality and efficiency were significantly reduced at 2 weeks. Poorer sleep quality was associated with greater next day pain intensity suggesting that sleep quality may be an important target for intervention.

How to: Measuring blood cytokines in biological psychiatry using commercially available multiplex immunoassays

Cytokines produced by both immune and non-immune cells are likely to play roles in the development and/or progression of psychiatric disorders. Indeed, many investigators have compared the blood cytokine levels in psychiatric patients with those of healthy controls or monitored their levels in patients during disease progression to identify biomarkers. Nevertheless, very few studies have confirmed that such cytokines remain stable in healthy individuals through periods of weeks and months. This is an important issue to consider before using blood cytokine levels as biomarkers of disease traits, disease state, or treatment response. Although multiplex assay technology represents an advance in identifying biomarkers because it allows simultaneous examination of large panels of analytes from a small volume of sample, it is necessary to verify whether these assays yield enough sensitivity and reproducibility when applied to the blood from neuropsychiatric patients. Therefore, we compared two multiplex immunoassays, the bead-based Luminex^® (Bio-Rad) and the electro-chemiluminescence-based V-plex^® (MesoScaleDiscovery), for the detection and quantification of 31 cytokines, chemokines and growth factors in both the sera and plasma of patients with major depressive episodes (MDE) and age- and sex-matched healthy control subjects during a 30-week period. Although both platforms exhibited low coefficients of variability (CV) between the duplicates in the calibration curves, the linearity was better in general for the V-PLEX^® platform. However, neither platform was able to detect the absolute values for all of the tested analytes. Among the 16 analytes that were detected by both assays, the intra-assay reproducibility was in general better with the V-PLEX^® platform. Although it is not a general rule that the results from sera and plasma will be correlated, consistent results were more frequent with the V-PLEX^® platform. Furthermore, the V-PLEX^® results were more consistent with the gold standard ELISA simplex assay for IL-6 in both sera and plasma. The intra-individual variability of the measurements, among the sera and plasma for the 4 samples harvested from each healthy individual, was low for Eotaxin, G-CSF, IL-4, IL-7, IL-9, IL-12p40, IL-12p70, IL-15, MIP-1β, PDGF-BB, TNF, TNF-β and VEGF, but intermediate or high for IFN-γ, IL-6, IL-8, IL-10, and IP10. Together, these data suggest that extreme caution is needed in translating the results of multiplex cytokine profiling into biomarker discovery in psychiatry.

Poor sleep quality is associated with greater circulating pro-inflammatory cytokines and severity and frequency of chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) symptoms in women

OBJECTIVE

Poor sleep quality has been linked to inflammatory processes and worse disease outcomes in the context of many chronic illnesses, but less is known in conditions such as chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME). This study examines the relationships between sleep quality, pro-inflammatory cytokines, and CFS/ME symptoms.

METHODS

Sixty women diagnosed with CFS/ME were assessed using the Pittsburgh Sleep Quality Index (PSQI), Fatigue Symptom Inventory (FSI) and Center for Disease Control and Prevention (CDC)-based CFS/ME symptom questionnaires. Circulating plasma pro-inflammatory cytokine levels were measured by ELISA. Multiple regression analyses examined associations between sleep, cytokines and symptoms, controlling for age, education, and body mass index.

RESULTS

Poor sleep quality (PSQI global score) was associated with greater pro-inflammatory cytokine levels: interleukin-1β (IL-1β) (β=0.258, p=0.043), IL-6 (β=0.281, p=0.033), and tumor necrosis factor-alpha (TNF-α) (β=0.263, p=0.044). Worse sleep quality related to greater fatigue severity (β=0.395, p=0.003) and fatigue-related interference with daily activities (β=0.464, p<0.001), and more severe and frequent CDC-defined core CFS/ME symptoms (β=0.499, p<0.001, and β=0.556, p<0.001, respectively).

CONCLUSIONS

Results underscore the importance of managing sleep-related difficulties in this patient population. Further research is needed to identify the etiology of sleep disruptions in CFS/ME and mechanistic factors linking sleep quality to symptom severity and inflammatory processes.

Association of systemic lupus erythematosus and sleep disorders: a nationwide population-based cohort study

Objective

Using a population-based cohort study, we investigated whether sleep disorders (SDs) increase the risk of systemic lupus erythematosus (SLE).

Patients and methods

We identified patients with SDs and a control cohort from 1998–2001 by using the Taiwan Longitudinal Health Insurance Database 2000. Two controls for each patient with an SD were selected and randomly frequency-matched according to age, gender, and index year. The follow-up person–years were estimated for the patients from the index date to SLE diagnosis, loss to follow-up, or the end of 31 December 2011. We used the Cox proportional hazards models to evaluate how SDs influence the risk of SLE after adjustments for demographic factors and comorbidities.

Results

A total of 144,396 subjects (48,132 SD cases and 96,264 controls) were followed for 1,477,055 person–years. The patients with SDs displayed higher incidence density rate of developing SLE than did the controls (1.03 vs 0.46 per 10,000 person–years). After adjustment for covariates, the patients with SDs exhibited a 2.20-fold higher adjusted hazard ratio (aHR) of developing SLE than the controls (95% confidence interval (CI) = 1.44–3.36). Women exhibited a greater prevalence of SDs and SLE compared to men. Patients with SDs aged 49 years and younger exhibited a significantly increased risk of SLE compared to the controls (aHR=2.30, 95% CI = 1.33–3.98). Patients with SDs living in urban areas exhibited a significantly increased risk of SLE.

Conclusion

This large population-based cohort study revealed that SDs increase the risk of SLE development.

The gut microbiome and the brain

The human gut microbiome impacts human brain health in numerous ways: (1) Structural bacterial components such as lipopolysaccharides provide low-grade tonic stimulation of the innate immune system. Excessive stimulation due to bacterial dysbiosis, small intestinal bacterial overgrowth, or increased intestinal permeability may produce systemic and/or central nervous system inflammation. (2) Bacterial proteins may cross-react with human antigens to stimulate dysfunctional responses of the adaptive immune system. (3) Bacterial enzymes may produce neurotoxic metabolites such as D-lactic acid and ammonia. Even beneficial metabolites such as short-chain fatty acids may exert neurotoxicity. (4) Gut microbes can produce hormones and neurotransmitters that are identical to those produced by humans. Bacterial receptors for these hormones influence microbial growth and virulence. (5) Gut bacteria directly stimulate afferent neurons of the enteric nervous system to send signals to the brain via the vagus nerve. Through these varied mechanisms, gut microbes shape the architecture of sleep and stress reactivity of the hypothalamic-pituitary-adrenal axis. They influence memory, mood, and cognition and are clinically and therapeutically relevant to a range of disorders, including alcoholism, chronic fatigue syndrome, fibromyalgia, and restless legs syndrome. Their role in multiple sclerosis and the neurologic manifestations of celiac disease is being studied. Nutritional tools for altering the gut microbiome therapeutically include changes in diet, probiotics, and prebiotics.

Quality of life in systemic sclerosis

Systemic sclerosis (SSc) is a chronic multi-system autoimmune disease associated with disability and reduced quality of life. There is no effective treatment or cure to SSc, so it is important improve global health of these patients and reduce morbidity and mortality associated with SSc. It was made a literature review about quality of life in patients with SSc, regarding the several factors that should be considered and evaluated when attending to SSc patients. It was also considered the validated scales and questionnaires used to measure outcomes in patients with SSc. We concluded that it is important to have an interdisciplinary approach to SSc patients considering the patient's cognitive representations of the disease and what they value most like mobility and hand function, pain, fatigue, sleep, depression and body image.

Influence of sleep deprivation and circadian misalignment on cortisol, inflammatory markers, and cytokine balance

Cortisol and inflammatory proteins are released into the blood in response to stressors and chronic elevations of blood cortisol and inflammatory proteins may contribute to ongoing disease processes and could be useful biomarkers of disease. How chronic circadian misalignment influences cortisol and inflammatory proteins, however, is largely unknown and this was the focus of the current study. Specifically, we examined the influence of weeks of chronic circadian misalignment on cortisol, stress ratings, and pro- and anti-inflammatory proteins in humans. We also compared the effects of acute total sleep deprivation and chronic circadian misalignment on cortisol levels. Healthy, drug free females and males (N=17) aged 20-41 participated. After 3weeks of maintaining consistent sleep-wake schedules at home, six laboratory baseline days and nights, a 40-h constant routine (CR, total sleep deprivation) to examine circadian rhythms for melatonin and cortisol, participants were scheduled to a 25-day laboratory entrainment protocol that resulted in sleep and circadian disruption for eight of the participants. A second constant routine was conducted to reassess melatonin and cortisol rhythms on days 34-35. Plasma cortisol levels were also measured during sampling windows every week and trapezoidal area under the curve (AUC) was used to estimate 24-h cortisol levels. Inflammatory proteins were assessed at baseline and near the end of the entrainment protocol. Acute total sleep deprivation significantly increased cortisol levels (p<0.0001), whereas chronic circadian misalignment significantly reduced cortisol levels (p<0.05). Participants who exhibited normal circadian phase relationships with the wakefulness-sleep schedule showed little change in cortisol levels. Stress ratings increased during acute sleep deprivation (p<0.0001), whereas stress ratings remained low across weeks of study for both the misaligned and synchronized control group. Circadian misalignment significantly increased plasma tumor necrosis factor-alpha (TNF-α), interleukin 10 (IL-10) and C-reactive protein (CRP) (p<0.05). Little change was observed for the TNF-α/IL-10 ratio during circadian misalignment, whereas the TNF-α/IL-10 ratio and CRP levels decreased in the synchronized control group across weeks of circadian entrainment. The current findings demonstrate that total sleep deprivation and chronic circadian misalignment modulate cortisol levels and that chronic circadian misalignment increases plasma concentrations of pro- and anti-inflammatory proteins.

Presurgical psychosocial predictors of acute postsurgical pain and quality of life in children undergoing major surgery

Limited research has examined presurgical risk factors for poor outcomes in children after major surgery. This longitudinal study examined presurgical psychosocial and behavioral factors as predictors of acute postsurgical pain intensity and health-related quality of life (HRQOL) in children 2 weeks after major surgery. Sixty children aged 10 to 18 years, 66.7% female, and their parent/guardian participated in the study. Children underwent baseline assessment of pain (daily electronic diary), HRQOL, sleep (actigraphy), and psychosocial factors (anxiety, pain catastrophizing). Caregivers reported on parental pain catastrophizing. Longitudinal follow-up assessment of pain and HRQOL was conducted at home 2 weeks after surgery. Regression analyses adjusting for baseline pain revealed that presurgery sleep duration (β = -.26, P < .05) and parental pain catastrophizing (β = .28, P < .05) were significantly associated with mean pain intensity reported by children 2 weeks after surgery, with shorter presurgery sleep duration and greater parental catastrophizing about child pain predicting greater pain intensity. Adjusting for baseline HRQOL, presurgery child state anxiety (β = -.29, P < .05) was significantly associated with HRQOL at 2 weeks, with greater anxiety predicting poorer HRQOL after surgery. In conclusion, child anxiety, parental pain catastrophizing, and sleep patterns are potentially modifiable factors that predict poor outcomes in children after major surgery.

PERSPECTIVE

This study addresses an important gap in literature, examining presurgical risk factors for poorer acute postsurgical outcomes in children undergoing major surgery. Knowledge of these factors will enable presurgical identification of children at risk for poorer outcomes and guide further research developing prevention and intervention strategies for these children.

Circadian rhythmicity, variability and correlation of interleukin-6 levels in plasma and cerebrospinal fluid of healthy men

BACKGROUND

Interleukin-6 (IL-6) is a cytokine with pleiotropic actions in both the periphery of the body and the central nervous system (CNS). Altered IL-6 secretion has been associated with inflammatory dysregulation and several adverse health consequences. However, little is known about the physiological circadian characteristics and dynamic inter-correlation between circulating and CNS IL-6 levels in humans, or their significance.

METHODS

Simultaneous assessment of plasma and cerebrospinal fluid (CSF) IL-6 levels was performed hourly in 11 healthy male volunteers over 24h, to characterize physiological IL-6 secretion levels in both compartments.

RESULTS

IL-6 levels showed considerable within- and between-subject variability in both plasma and CSF, with plasma/CSF ratios revealing consistently higher levels in the CSF. Both CSF and plasma IL-6 levels showed a distinctive circadian variation, with CSF IL-6 levels exhibiting a main 24h, and plasma a biphasic 12h, circadian component. Plasma peaks were roughly at 4 p.m. and 4 a.m., while the CSF peak was at around 7 p.m. There was no correlation between coincident CSF and plasma IL-6 values, but evidence for significant correlations at a negative 7-8h time lag.

CONCLUSIONS

This study provides evidence in humans for a circadian IL-6 rhythm in CSF and confirms prior observations reporting a plasma biphasic circadian pattern. Our results indicate differential IL-6 regulation across the two compartments and are consistent with local production of IL-6 in the CNS. Possible physiological significance is discussed and implications for further research are highlighted.

Prolonged sleep fragmentation of mice exacerbates febrile responses to lipopolysaccharide

BACKGROUND

Sleep disruption is a frequent occurrence in modern society. Whereas many studies have focused on the consequences of total sleep deprivation, few have investigated the condition of sleep disruption.

NEW METHOD

We disrupted sleep of mice during the light period for 9 consecutive days using an intermittently rotating disc.

RESULTS

Electroencephalogram (EEG) data demonstrated that non-rapid eye movement (NREM) sleep was severely fragmented and REM sleep was essentially abolished during the 12h light period. During the dark period, when sleep was not disrupted, neither NREM sleep nor REM sleep times differed from control values. Analysis of the EEG revealed a trend for increased power in the peak frequency of the NREM EEG spectra during the dark period. The fragmentation protocol was not overly stressful as body weights and water consumption remained unchanged, and plasma corticosterone did not differ between mice subjected to 3 or 9 days of sleep disruption and home cage controls. However, mice subjected to 9 days of sleep disruption by this method responded to lipopolysaccharide with an exacerbated febrile response.

COMPARISON WITH EXISTING METHODS

Existing methods to disrupt sleep of laboratory rodents often subject the animal to excessive locomotion, vibration, or sudden movements. This method does not suffer from any of these confounds.

CONCLUSIONS

This study demonstrates that prolonged sleep disruption of mice exacerbates febrile responses to lipopolysaccharide. This device provides a method to determine mechanisms by which chronic insufficient sleep contributes to the etiology of many pathologies, particularly those with an inflammatory component.

Whole blood genome-wide gene expression profile in males after prolonged wakefulness and sleep recovery

Although the specific functions of sleep have not been completely elucidated, the literature has suggested that sleep is essential for proper homeostasis. Sleep loss is associated with changes in behavioral, neurochemical, cellular, and metabolic function as well as impaired immune response. Using high-resolution microarrays we evaluated the gene expression profiles of healthy male volunteers who underwent 60 h of prolonged wakefulness (PW) followed by 12 h of sleep recovery (SR). Peripheral whole blood was collected at 8 am in the morning before the initiation of PW (Baseline), after the second night of PW, and one night after SR. We identified over 500 genes that were differentially expressed. Notably, these genes were related to DNA damage and repair and stress response, as well as diverse immune system responses, such as natural killer pathways including killer cell lectin-like receptors family, as well as granzymes and T-cell receptors, which play important roles in host defense. These results support the idea that sleep loss can lead to alterations in molecular processes that result in perturbation of cellular immunity, induction of inflammatory responses, and homeostatic imbalance. Moreover, expression of multiple genes was downregulated following PW and upregulated after SR compared with PW, suggesting an attempt of the body to re-establish internal homeostasis. In silico validation of alterations in the expression of CETN3, DNAJC, and CEACAM genes confirmed previous findings related to the molecular effects of sleep deprivation. Thus, the present findings confirm that the effects of sleep loss are not restricted to the brain and can occur intensely in peripheral tissues.

Sleep disturbances and interleukin 6 receptor inhibition in rheumatoid arthritis

OBJECTIVE

Interleukin 6 (IL-6)-mediated interactions have been associated with sleep disturbances in healthy subjects. In this pilot study we examined whether administration of the IL-6 receptor antagonist tocilizumab in patients with rheumatoid arthritis (RA) affects sleep disturbances.

METHODS

Fifteen patients (13 women) with sleep disturbances at baseline received 6 monthly infusions of tocilizumab 8 mg/kg for moderately or severely active RA. Sleep quality was assessed by Pittsburgh Sleep Quality Index (PSQI), daytime sleepiness by Epworth Sleepiness Scale, disease activity by the 28-joint Disease Activity Score-erythrocyte sedimentation rate, functional disability by Health Assessment Questionnaire Disability Index (HAQ-DI), and fatigue by the Functional Assessment of Chronic Illness Therapy (FACIT-Fatigue Scale; FFS) at baseline and first, second, third, and sixth month of treatment. Medications used before enrollment remained unchanged during followup.

RESULTS

Sleep quality improved and daytime sleepiness decreased significantly at first-month assessment (p < 0.00001 and p < 0.004, respectively, by repeated measurement analysis) compared to baseline, and these changes became more evident through 6 months. Disease activity decreased, fatigue decreased, and functional status improved significantly. Changes in PSQI score over time were not associated with the corresponding changes in DAS28-ESR (r = 0.37, p = 0.17), but correlated significantly with HAQ-DI changes (r = 0.60, p = 0.02) and marginally with changes in FFS scores (r = -0.46, p = 0.08).

CONCLUSION

Improvement of sleep quality after tocilizumab treatment in patients with RA does not appear to directly result from decreased disease activity, further suggesting that aberrant IL-6 regulation is associated with sleep disturbances.

Neurochemical and neuropharmacological aspects of circadian disruptions: an introduction to asynchronization

Circadian disruptions are common in modern society, and there is an urgent need for effective treatment strategies. According to standard diagnostic criteria, most adolescents showing both insomnia and daytime sleepiness are diagnosed as having behavioral-induced sleep efficiency syndrome resulting from insomnia due to inadequate sleep hygiene. However, a simple intervention of adequate sleep hygiene often fails to treat them. As a solution to this clinical problem, the present review first overviews the basic neurochemical and neuropharmachological aspects of sleep and circadian rhythm regulation, then explains several circadian disruptions from similar viewpoints, and finally introduces the clinical notion of asynchronization. Asynchronization is designated to explain the pathophysiology/pathogenesis of exhibition of both insomnia and hypersomnia in adolescents, which comprises disturbances in various aspects of biological rhythms. The major triggers for asynchronization are considered to be a combination of light exposure during the night, which disturbs the biological clock and decreases melatonin secretion, as well as a lack of light exposure in the morning, which prohibits normal synchronization of the biological clock to the 24-hour cycle of the earth and decreases the activity of serotonin. In the chronic phase of asynchronization, involvement of both wake- and sleep-promoting systems is suggested. Both conventional and alternative therapeutic approaches for potential treatment of asynchronization are suggested.

Evidence for neuroinflammatory and microglial changes in the cerebral response to sleep loss

STUDY OBJECTIVES

Sleep loss has pro-inflammatory effects, but the roles of specific cell populations in mediating these effects have not been delineated. We assessed the modulation of the electroencephalographic and molecular responses to sleep deprivation (S-DEP) by minocycline, a compound that attenuates microglial activation occurring in association with neuroinflammatory events.

DESIGN

Laboratory rodents were subjected to assessment of sleep and wake in baseline and sleep deprived conditions.

PARTICIPANTS

Adult male CD-1 mice (30-35 g) subjected to telemetric electroencephalography.

INTERVENTIONS

Minocycline was administered daily. Mice were subjected to baseline data collection on the first day of minocycline administration and, on subsequent days, 2 S-DEP sessions, 1 and 3 h in duration, followed by recovery sleep. Following EEG studies, mice were euthanized either at the end of a 3 h S-DEP or as time-of day controls for sampling of brain messenger RNAs. Gene expression was measured by real-time polymerase chain reaction.

MEASUREMENTS AND RESULTS

Minocycline-treated mice exhibited a reduction in time spent asleep, relative to saline-treated mice, in the 3-h interval immediately after administration. S-DEP resulted in an increase in EEG slow wave activity relative to baseline in saline-treated mice. This response to S-DEP was abolished in animals subjected to chronic minocycline administration. S-DEP suppressed the expression of the microglial-specific transcript cd11b and the neuroinflammation marker peripheral benzodiazepine receptor, in the brain at the mRNA level. Minocycline attenuated the elevation of c-fos expression by S-DEP. Brain levels of pro-inflammatory cytokine mRNAs interleukin-1β (il-1β), interleukin-6 (il-6), and tumor necrosis factor-α (tnfα) were unaffected by S-DEP, but were elevated in minocycline-treated mice relative to saline-treated mice.

CONCLUSIONS

The anti-neuroinflammatory agent minocycline prevents either the buildup or expression of sleep need in rodents. The molecular mechanism underlying this effect is not known, but it is not mediated by suppression of il-1β, il-6, and tnfα at the transcript level.

Prevalence and correlates of sleep disturbance in systemic sclerosis--results from the UCLA scleroderma quality of life study

OBJECTIVE

Rheumatologic disorders are associated with sleep disturbances. This study examines sleep disturbance correlates in patients with SSc.

METHODS

Participants are 180 SSc patients in an observational study. At baseline, patients completed the Medical Outcomes Study Sleep measure (MOS-Sleep scale). In addition, patients were administered other patient-reported outcome (PRO) measures including the 36-item short form (SF-36), HAQ disability index (HAQ-DI), Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-Fatigue), Center for Epidemiologic Studies Depression (CESD) scale and a University of California at Los Angeles Scleroderma Clinical Trial Consortium Gastrointestinal Tract Questionnaire (UCLA SCTC GIT 2.0). Descriptive statistics were assessed for six scales of MOS-Sleep and the 9-item sleep problem index (SLP-9; a composite index). We computed Spearman's rank-order correlations between the MOS-Sleep scales and the HAQ-DI, FACIT-Fatigue, CESD, SSc-SCTC GIT 2.0 and SF-36 scales. In addition, we developed a regression model to assess predictors of SLP-9 scores. Covariates included demographics, physician variables of disease severity and patient-reported variables of worsening symptoms and the PRO measures.

RESULTS

SSc patients reported a mean (s.d.) of 7.1 (1.73) h of sleep a night. Patients reported worse scores on four of six scales (except for snoring and sleep quantity) compared with the US general population (P < 0.001). SLP-9 was correlated with worsening pain and dyspnoea over the past 1 month, reflux scale of the UCLA SCTC GIT 2.0, CESD and FACIT-Fatigue (ρ 0.26-0.56). In the stepwise multivariate regression model, the CESD, worsening dyspnoea and reflux scale were significantly associated with SLP-9 index.

CONCLUSION

Sleep disturbances are common in SSc and are associated with worsening dyspnoea, depressed mood and severity of reflux symptoms.

Allergic rhinitis: indicators of quality of life

The objective of this review was to present evidence of the relationship between allergic rhinitis and impairment of quality of life. The data sources were original articles, reviews and consensus statements entered into the Medline and LILACS databases between 1997 and 2008. The following search terms were used: 'allergic rhinitis'; 'quality of life'; and 'sleep disorders'. Quality of life is often impaired in patients with allergic rhinitis, due to the classic symptoms of the disease (sneezing, pruritus, rhinorrhea and nasal obstruction). In addition, the pathophysiology of allergic rhinitis often disrupts sleep, leading to fatigue, irritability, memory deficits, daytime sleepiness and depression. The total burden of this disease goes beyond impairment of physical and social functioning. It has also a financial impact, which becomes greater when we consider the evidence that allergic rhinitis is a possible causal factor of comorbidities, such as asthma and sinusitis. Nasal obstruction, the most prominent symptom, is associated with sleep disorders, which can have a profound effect on mental health, learning, behavior and attention. Finally, allergic rhinitis-a chronic condition that affects adults, adolescents and children-is often underdiagnosed or inadequately treated. The deleterious impact that allergic rhinitis-related sleep disorders have on patient capacity to perform activities of daily living is an important component of the morbidity of the disease. With an accurate diagnosis, there are various available treatments that can reduce the burden of allergic rhinitis.

Effects of sleep and circadian rhythm on the human immune system

Many immune parameters show systematic fluctuations over the 24-h day in human blood. Circulating naive T-cells and production of proinflammatory cytokines, like interleukin-12 (IL-12), peak during nighttime, whereas cytotoxic effector leukocytes and production of the anti-inflammatory cytokine IL-10 peak during daytime. These temporal changes originate from a combined influence of the circadian system and sleep. Both brain functions act synergistically and share neuroendocrine effector mechanisms to convey control over immune functions. Sympathetic tone and cortisol levels show a circadian nadir during nighttime and are further suppressed by sleep, whereas growth hormone and prolactin show a circadian peak during nighttime and are further enhanced by sleep. Thus, the circadian system and sleep jointly evoke a unique endocrine constellation that is extremely effective in inducing changes in leukocyte traffic and a shift toward proinflammatory type 1-cytokines during the nocturnal period of sleep, that is, an action with strong clinical implications.

Sleep viewed as a state of adaptive inactivity

Sleep is often viewed as a vulnerable state that is incompatible with behaviours that nourish and propagate species. This has led to the hypothesis that sleep has survived because it fulfills some universal, but as yet unknown, vital function. I propose that sleep is best understood as a variant of dormant states seen throughout the plant and animal kingdoms and that it is itself highly adaptive because it optimizes the timing and duration of behaviour. Current evidence indicates that ecological variables are the main determinants of sleep duration and intensity across species.

Enhancing influence of intranasal interleukin-6 on slow-wave activity and memory consolidation during sleep

The cytokine IL-6 has been considered to exert neuromodulating influences on the brain, with promoting influences on sleep. Sleep enhances the consolidation of memories, and, in particular, late nocturnal sleep also represents a period of enhanced IL-6 signaling, due to a distinctly enhanced availability of soluble IL-6 receptors during this period, enabling trans-signaling of IL-6 to neurons. Thus, a contribution of IL-6 to sleep-dependent memory consolidation is hypothesized. To test this hypothesis, we compared effects of intranasally administered IL-6 (vs. placebo) on sleep-dependent consolidation of declarative (neutral and emotional texts, 2-dimensional object location) and procedural (finger sequence tapping) memories in 17 healthy young men. IL-6 distinctly improved the sleep-related consolidation of emotional text material (P<0.03), which benefits mostly from sleep in the second night-half, in which rapid eye movement sleep (REM) dominates the non-REM-REM sleep cycle. During this second night-half, the amount of electroencephalogram slow-wave activity (0.5-4 Hz) distinctly increased after IL-6 (P<0.01). Other types of memory were not affected. The ability of IL-6 to enhance sleep-associated emotional memory consolidation highlights an example of a functional interaction between the central nervous and immune system.

The hyperarousal model of insomnia: a review of the concept and its evidence

Primary insomnia is defined as difficulties in falling asleep, maintaining sleep or non-restorative sleep accompanied by significantly impaired daytime functioning in the absence of a specific physical, mental or substance-related cause. The current review provides substantial support for the concept that hyperarousal processes from the molecular to the higher system level play a key role in the pathophysiology of primary insomnia. Autonomous, neuroendocrine, neuroimmunological, electrophysiological and neuroimaging studies demonstrate increased levels of arousal in primary insomnia during both night and daytime. In the light of neurobiological theories of sleep-wake regulation, primary insomnia may be conceptualized as a final common pathway resulting from the interplay between a genetic vulnerability for an imbalance between arousing and sleep-inducing brain activity, psychosocial/medical stressors and perpetuating mechanisms including dysfunctional sleep-related behavior, learned sleep preventing associations and other cognitive factors like tendency to worry/ruminate.

How (and why) the immune system makes us sleep

Good sleep is necessary for physical and mental health. For example, sleep loss impairs immune function, and sleep is altered during infection. Immune signalling molecules are present in the healthy brain, where they interact with neurochemical systems to contribute to the regulation of normal sleep. Animal studies have shown that interactions between immune signalling molecules (such as the cytokine interleukin 1) and brain neurochemical systems (such as the serotonin system) are amplified during infection, indicating that these interactions might underlie the changes in sleep that occur during infection. Why should the immune system cause us to sleep differently when we are sick? We propose that the alterations in sleep architecture during infection are exquisitely tailored to support the generation of fever, which in turn imparts survival value.

Cortistatin--functions in the central nervous system

Cortistatin (CST) is a neuropeptide from the somatostatin (SRIF)/urotensin (UII) family named after its predominantly cortical expression and ability to depress cortical activity, which was discovered a decade ago. In vitro assays show CST is able to bind all five cloned somatostatin receptors and shares many pharmacological and functional properties with SRIF. However, distinct from SRIF, CST has been shown to induce slow-wave sleep, reduce locomotor activity, and activate cation selective currents not responsive to somatostatin. Different lines of evidence also indicate that CST, like SRIF, is involved in learning and memory processes. CST-14 may also function as an endogenous anti-convulsant. In addition to its role in cortical synchronization, CST-14 has emerged as an important mediator of immunity and inflammation. This review will cover some of the basic properties of CST in the brain, and will discuss new data on the role of CST in cortical activity.

Sleep and inflammation

Among adults in the United States, sleep durations appear to have decreased in recent years. Inadequate sleep and sleep deprivation cause numerous neurobehavioral and physiological changes. A number of recent studies have reported associations between disrupted sleep/sleep deprivation and inflammatory responses, although the physiological mechanisms underlying these relationships remain unclear. Alterations in sleep due to lifestyle factors, the aging process, and disease states have all been associated with increases in a range of inflammatory markers. Several of these inflammatory processes have been associated with reduced health status (e.g., C-reactive protein and cardiovascular disease). Thus, maintaining adequate sleep duration and quality through good sleep habits and treatment of sleep disorders may reduce inflammatory processes associated with aging and increase the wellness phenotype.

Differences in cytokines between non-suicidal patients and suicidal patients in major depression

Several studies have shown that there is an imbalance between pro-inflammatory and anti-inflammatory cytokines in major depressive disorder (MDD). However, little is known about the role of cytokines in suicide. In the present study, amounts of IL-6, IL-2, IFN-gamma, IL-4, and TGF-beta1 produced by mitogen-stimulated whole blood were measured in 36 MDD patients who had recently attempted suicide, 33 non-suicidal MDD patients, and 40 normal controls. The severity of depression symptoms and suicidal behaviors was evaluated using Hamilton's depression rating scale (HDRS), the Lethality Suicide Attempt Rating Scale (LSARS), and the Risk-Rescue Rating (RRR). Non-suicidal MDD patients had significantly higher IL-6 production than suicidal MDD patients and normal controls (p<0.001). Suicidal MDD patients had significantly lower IL-2 compared with non-suicidal patients and normal controls (p<0.001). Both MDD groups, with or without attempted suicide, had significantly lower IFN-gamma and IL-4 and higher TGF-beta1 production. HDRS scores had significant positive correlations with IL-6, IFN-gamma, and the Th1/Th2 ratio and significant negative correlations with IL-4 in non-suicidal depression patients (p<0.005); however, these correlations did not hold true for suicidal patients. Suicidal MDD patients had no significant correlations between the LSARS or RRR scores and cytokine release. Our findings suggest that the immune response has distinct differences between non-suicidal patients and suicidal patients. Non-suicidal MDD may be associated with increased IL-6 production and a Th1/Th2 imbalance with a shift to Th1, while suicidal MDD may be associated with decreased IL-2.

Sleep enhances serum interleukin-7 concentrations in humans

Growing evidence points towards a beneficial effect of sleep on immune function. Human studies indicate that the T cell mediated adaptive immune function including formation of antigen specific antibodies is facilitated by sleep. Along this line, here we aimed to dissociate the effect of sleep and circadian rhythm on circulating interleukin-7 (IL-7) and interleukin-15 (IL-15). These cytokines play a key role in the homeostatic regulation of naïve and memory T cell numbers and are critical for the differentiation of memory T cells. Serum IL-7 concentration and expression of membrane-bound IL-15 (mIL-15) on CD14(+) monocytes were measured in 18 men on two occasions: once during a regular 24-h sleep-wake cycle and another time during a 24-h period of continuous wakefulness. During sleep and especially during late sleep serum IL-7 concentrations were distinctly increased as compared to wakefulness (p<0.05). mIL-15 density on monocytes remained unchanged by sleep. The sleep-dependent increase in IL-7 concentration was associated with increased REM sleep, but did not correlate with concentrations of GH, cortisol or norepinephrine during sleep. The findings concur with the notion of a supportive influence of sleep on T cell function related to formation of T cell memory.

Effect of environmental temperature on sleep, locomotor activity, core body temperature and immune responses of C57BL/6J mice

Ambient temperature exerts a prominent influence on sleep. In rats and humans, low ambient temperatures generally impair sleep, whereas higher temperatures tend to promote sleep. The purpose of the current study was to evaluate sleep patterns and core body temperatures of C57BL/6J mice at ambient temperatures of 22, 26 and 30 degrees C under baseline conditions, after sleep deprivation (SD), and after infection with influenza virus. C57BL/6J mice were surgically implanted with electrodes for recording electroencephalogram (EEG) and electromyogram (EMG) and with intraperitoneal transmitters for recording core body temperature (T(c)) and locomotor activity. The data indicate that higher ambient temperatures (26 and 30 degrees C) promote spontaneous slow wave sleep (SWS) in association with reduced delta wave amplitude during SWS in C57BL/6J mice. Furthermore, higher ambient temperatures also promote recuperative sleep after SD. Thus, in mice, higher ambient temperatures reduced sleep depth under normal conditions, but augmented the recuperative response to sleep loss. Mice infected with influenza virus while maintained at 22 or 26 degrees C developed more SWS, less rapid eye movement sleep, lower locomotor activity and greater hypothermia than did mice maintained at 30 degrees C during infection. In addition, despite equivalent viral titers, mice infected with influenza virus at 30 degrees C showed less leucopenia and lower cytokine induction as compared with 22 and 26 degrees C, respectively, suggesting that less inflammation develops at the higher ambient temperature.

Poor sleep the night before an experimental stressor predicts reduced NK cell mobilization and slowed recovery in healthy women

Sleep is important for health; however, poor sleep is a growing problem in many Western societies, particularly among women. Alterations in immune function following poor sleep (defined by duration and disruption) may be linked to ill health. Not yet investigated are the possible effects on stress-induced mobilization of lymphocytes. As natural killer (NK) cells are particularly responsive to acute stress, the present study examined whether sleep period duration and percentage of time awake after sleep onset (WASO) the night before a laboratory stressor would predict reduced NK cell mobilization. Sleep was monitored by actigraphy in 39 healthy women. NK cell peripheral blood numbers were determined at baseline (post-20 min rest), 4 min into a Stroop task, immediately post-task and 30 min after task completion. Participants with high WASO had significantly less NK cell mobilization to the stressor and failed to return to baseline levels after 30 min compared to women with low WASO. No effects were found for sleep period duration. Findings raise the possibility that inadequate NK cell mobilization to, and poor recovery from acute stress may be one pathway by which sleep could impact health.

The importance of rhinitis on sleep, daytime somnolence, productivity and fatigue

PURPOSE OF REVIEW

The goal of treatment of allergic rhinitis should include improvement of daytime and nighttime symptoms, sleep, and quality of life. Congestion from allergic rhinitis is associated with decreased learning and productivity at work and school and a reduced quality of life. The release of inflammatory mediators and activation of inflammatory cells results in nasal congestion, causing disrupted sleep and subsequent daytime somnolence.

RECENT FINDINGS

This review presents evidence that allergic rhinitis causes sleep disruption, and discusses the pathophysiology of this process. The medications used to treat allergic rhinitis and their ability to improve sleep in patients with allergic rhinitis are reviewed.

SUMMARY

Some allergic rhinitis medications can be sedating; therefore, it is important to treat allergic rhinitis with medications that improve symptoms while producing few adverse effects. Medications such as the second-generation antihistamines and anticholinergic drugs are well tolerated, but have little effect on congestion. Intranasal corticosteroids reduce congestion, improve sleep and sleep problems, and reduce daytime sleepiness, fatigue, and inflammation. Recently, montelukast, a leukotriene receptor antagonist, has been added to the therapies approved for allergic rhinitis. Montelukast significantly improves both daytime and nighttime symptoms.